/*
 * Copyright (c) 2022 Huawei Device Co., Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
export function csTdfs(j, k, w, head, next, post, stack) {
  // variables
  var top = 0; // place j on the stack

  w[stack] = j; // while (stack is not empty)

  while (top >= 0) {
    // p = top of stack
    var p = w[stack + top]; // i = youngest child of p

    var i = w[head + p];

    if (i === -1) {
      // p has no unordered children left
      top--; // node p is the kth postordered node

      post[k++] = p;
    } else {
      // remove i from children of p
      w[head + p] = w[next + i]; // increment top

      ++top; // start dfs on child node i

      w[stack + top] = i;
    }
  }

  return k;
}